By Anick Jesdanun
The Associated Press

NEW YORK - The premise sounds simple: To cut down on junk e-mail, simply submit your addresses to a "do-not-spam" list that marketers would have to check to avoid fines.

With more than 50 million phone numbers already on a federal do-not-call list, many e-mail users are eager for a no-spam counterpart.

But don't hold out much hope, even if one is created. Phone and e-mail systems - and the marketers who employ them - are fundamentally different.

"It's beyond even an apples-to-oranges comparison," said Nicholas Graham, a spokesman for America Online Inc.

Even supporters say a no-spam list would be no panacea.

"I don't think anyone out there is going to tell you that a do-not-e-mail registry is going to be as effective as a do-not-call registry," said Matthew Prince, co-founder of Unspam LLC, a Chicago startup that developed technology to run such an anti-spam list.

Not that the cautions are stopping the efforts.

Sen. Charles Schumer, D-N.Y., has a bill to create a national do-not-spam list. State senates in Louisiana and Michigan have passed similar legislation, and bills have been introduced in other states. Violators could be fined - and in Michigan, even sent to jail.

An industry trade group, the Direct Marketing Association, already keeps a no-spam list of 700,000 e-mail addresses that its members are asked to heed. Also, at least three private companies started their own no-spam lists this year. Two of them charge the public for inclusion.

But these lists have no enforcement power.

Bryan Hunter, who runs the $9.95-a-year Remove.org, claims lists such as his help marketers better target pitches. "They realize these are people who aren't going to buy their products," he said.

But John Levine, board member of the Coalition Against Unsolicited Commercial Email, dismisses such companies as toothless. Without the legal standing of a government list, such private efforts "range from naively ineffective to complete scams," he said.

Michigan Attorney General Mike Cox has threatened a deceptive-marketing lawsuit against Remove.org.

Meanwhile, the chairman of the Federal Trade Commission, which runs the do-not-call list, doubts whether a government-run counterpart for spam would work.

E-mail systems are spread out around the globe, and information about the e-mail sender is easy to fake. The phone network is centralized and regulated.